Yesterday Iran's supreme leader and commander-in-chief of its armed forces, Ayatollah Ali Khamenei, was reported as assuring that Tehran would not launch hostilities against the Taliban regime, which after two years of civil war now controls the bulk of Afghanistan.
But there was no explaining why these remarks only appeared in print three days after they were apparently made, and why so large an Iranian force, supported by 80 Soviet-built T-72 tanks, 90 heavy artillery pieces and dozens of strike aircraft had moved last week to the country's eastern frontier.
According to some analysts, the incongruity could be a sign of further splits within a divided Tehran regime, between a faction that believes it is pointless for Iran to be dragged into a conflict that it has no more chance of winning than Britain, the Soviet Union and every other outsider who has previously tried to tame Afghanistan, and hardliners who believe they have a chance to undermine Taliban with a stinging military defeat.
From the Afghan side, a Taliban spokesman warned that any incursion would be responded to in kind. Any war "would have a domino effect", declared Noorullah Zadran, the movement's New York spokesman. It would "turn the entire region into a fireball", and involve "the most deadly weapons which have never been used in that area".
The immediate cause of confrontation is the fate of 11 Iranian diplomats who vanished when Taliban fighters captured the strategic northern city of Mazar-e Sharif last month and, according to Amnesty International, massacred thousands of people in the area.
Last week, five Iranian truck drivers seized at Mazar were released and returned home. But until yesterday, no amount of pressure has been able to extract word from the Afghan side on what befell the diplomats and a score of other missing Iranian nationals. Unofficially, some Taliban officials admit these could have been killed by "renegades" within the movement's ranks.
But no less a motivation for Tehran is its intense dislike and jealousy - partly for political and partly for religious reasons - of the Taliban regime, whose zone of control has now almost reached the frontier. Shia Iran is anxious to protect remaining Shia Muslims in those pockets of Afghanistan that have still not been brought to heel by the Taliban, who are Sunni Muslims.
Iran has also been among the staunchest supporters of Afghanistan's former president Burhanuddin Rabbani, deposed in 1996, but still regarded as the country's legitimate ruler by the United Nations.
The Taliban government, recognised only by Pakistan, Saudi Arabia and the United Arab Emirates, accuses Iran of fomenting Afghan opposition groups who have taken refuge there.
Iran is not the only country watching very closely how events unfold. Following in the footsteps of several other senior opposition figures, Mr Rabbani arrived yesterday in Ankara to meet President Suleiman Demirel of Turkey, a country that has strong ethnic and linguistic links with Afghanistan's Uzbek minority, still resisting the Taliban in the mountainous heart of the country.
Last, but not least, of the interested spectators is the United States. The latest tensions were first revealed by American intelligence analysts, who are monitoring events in the region especially closely after the missile attack, on 20 August, on the headquarters in south eastern Afghanistan of Osama bin Laden, the alleged mastermind of last month's terrorist attacks on the US embassies in Nairobi and Dar es Salaam.Reuse content